Q5

[yingxxgao]

Hi could anyone please explain how B is supported? Is it because of the sentence " low-intensity fires maintained open forests"? How is density inferable here? Why is D wrong?

Thanks!

[jewels0602]

D is wrong because the diversity of plant species isn't mentioned anywhere in the passage, so it's difficult to infer on it... B is correct because of two sets of lines (I have kindle version without the lines... but one set starts in the middle of second paragraph, "Ancient ponderosa forests, for example, were stable... clearing the understory of brush and young trees.", and the line that starts mid-way in the third paragraph, "...many forests, including ponderosa forests, have now been free of fire for 50 years or longer,...")

By connecting them, we see that if they haven't have fires in so long, there are probably lots of young trees and understory of brushes around, moreover, we also get that these forests, when naturally allowed to burn, have a fire every 5-25 years that clears up the forest, so if there has been no fire for 50 years, then most definitely the forest is going to be comparatively VERY dense; it has missed at least two fires that reduce some of the fuel in form of plants... hence B.

I hope this explanation helps...

[rinagoldfield]

Thanks for your posts!
Jewels, I agree with your support for B:
"Ancient ponderosa forests, for example, were stable... clearing the understory of brush and young trees." (lines 15-16)

As for the other choices:

(A) and (C) are out of scope; the passage doesn’t address genetics or weather patterns.
(D) is also unsupported. If anything, we know that these low-intensity fires killed off brush.
(E) is the opposite of what we are looking for. We know that animals get killed in the big fires, but escape the low-intensity fires (lines 23-25)

Hope that helps.